By John Oncea, Editor
LiDAR – is there anything it can’t do? Invented in the 1960s on the heels of the invention of the laser, LiDAR became commercially viable in the late 1980s. Today, it’s omnipresent, allowing us to do things we’ve never seen before in ways we never imagined.
“Everybody loves Raymond. I go to work and people shoot at me. Raymond goes to work and people do the wave. Then he sits down, has a hot dog, doodles on a piece of paper, and they give him a trophy.” – Robert Barone, talking about his younger brother Ray on the very first episode of Everybody Loves Raymond. *
LiDAR is photonics’ Ray Barone; it seems as if everybody loves it. ** It’s a topic that consistently pops up among the most popular on our site. This article from August has been one of the most-viewed pieces I’ve written. Heck, even this article my predecessor Abby Proch wrote nearly two years ago is still getting views.
So why does everybody love LiDAR?
* The title of the show Everybody Loves Raymond originated from a response Romano’s real-life brother, Richard, made after Ray won a CableACE stand-up award: “I had a day where people were shooting at me, and you're bringing home trophies. Everybody loves Raymond, don't they?”
** Everyone except for Elon Musk, maybe. But, according to The Street, Musk’s “strange aversion to LiDAR” is what is “ currently preventing Tesla from making that much-anticipated jump to a Level Three system (hands off, eyes off).” A Level Three system allows for conditional automation and requires a vehicle “to have a baked-in redundancy if the main system fails. This redundancy allows for the ‘eyes-off’ approach.” In short, without LiDAR Tesla’s backup sensor is the driver meaning his or her eyes have to be on the road while the car is in motion.
Light Detection and Ranging (LiDAR) *** “is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth,” according to the National Oceanic and Atmospheric Administration (NOAA). “These light pulses — combined with other data recorded by the airborne system — generate precise, three-dimensional information about the shape of the Earth and its surface characteristics.”
LiDAR equipment includes a laser, a scanner, a Global Positioning System (GPS), and an Inertial Navigation System (INS) with helicopters and aircraft serving as the most commonly used platforms for acquiring LiDAR over broad areas.
According to The National Ecological Observatory Network, “LiDAR is an active remote sensing system. An active system means that the system itself generates energy – in this case, light – to measure things on the ground. In a LiDAR system, light is emitted from a rapidly firing laser. You can imagine light quickly strobing from a laser light source. This light travels to the ground and reflects off of things like buildings and tree branches. The reflected light energy then returns to the LiDAR sensor where it is recorded.
“A LiDAR system measures the time it takes for emitted light to travel to the ground and back. That time is used to calculate the distance traveled. Distance traveled is then converted to elevation. These measurements are made using the key components of a lidar system including a GPS that identifies the X, Y, Z location of the light energy and an Inertial Measurement Unit (IMU) that provides the orientation of the plane in the sky.”
LiDAR is used in as many industries as there are industries. It is valued by researchers, scientists, and others for a variety of reasons, including:
- Precision: LiDAR systems provide highly accurate and detailed 3D measurements of the environment, making them invaluable for applications such as autonomous vehicles, precision agriculture, and surveying.
- Range: LiDAR can operate effectively over a wide range, from a few inches to several miles, depending on the specific technology and equipment used.
- Versatility: LiDAR can be used in diverse fields, including robotics, forestry, archaeology, environmental monitoring, and urban planning, making it a versatile tool for a wide range of applications.
- Safety: LiDAR technology is crucial for enabling advanced driver assistance systems (ADAS) and self-driving cars, which have the potential to improve road safety by reducing accidents caused by human error.
- Innovation: Ongoing advancements in LiDAR technology have made it more accessible, affordable, and capable, leading to further innovation in a variety of industries.
- Environmental Benefits: LiDAR can be used for environmental monitoring and conservation efforts, helping researchers and organizations track changes in landscapes, forests, and ecosystems.
- Research and Exploration: LiDAR is used in scientific research and exploration, such as mapping the seafloor, studying glaciers, and conducting archaeological surveys of historical sites.
While LiDAR has received widespread attention and positive recognition for its capabilities, it's essential to remember that it also has its challenges. Cost, size, and weather-related limitations can affect LiDAR technology’s adoption and implementation in certain applications. Nevertheless, LiDAR continues to play a significant role in shaping the future of technology and data collection in many industries.
*** I chose to go with the acronym LiDAR, but it also appears in print as lidar, LIDAR, LIDaR, and LADAR. LiDAR was originally called Colidar, an acronym for coherent light detecting and ranging, and was derived from the term radar, which stands for radio detection and ranging. The first mention of lidar as a stand-alone word came in 1963 and the capitalized acronyms, LIDAR and LiDAR, showed up in some publications beginning in the 1980s. No consensus exists on the “right” term. The United States Geological Survey uses both LIDAR and lidar and the New York Times predominantly uses lidar, though contributing news feeds such as Reuters may use Lidar.
Gas, NASA, And Garbage: Guess What They Have In Common
So, we’ve gone on a bit about what LiDAR is, how it works, and some of the benefits it provides. “But, John,” you may be asking. “What are some real-life examples of how LiDAR actually works?” I’m glad you asked.
First up, the natural gas industry where drones have shown promising initial results in detecting leaks in the upstream and midstream, and as a result, according to the American Gas Association (AGA), some natural gas utilities are now testing the use of drones as part of their leak detection and repair (LDAR) efforts.
Although it's difficult to quantify the full benefits of drones to leak detection projects at this early stage, it's clear that they have the potential to revolutionize the way the industry addresses leaks. Drones also can increase the scale and reliability of LDAR efforts and improve safety, which is a crucial factor in the industry.
“Currently, the technology being piloted involves drones being equipped with a natural gas detector onboard that collects samples, measuring natural gas concentrations within those samples in parts per million (ppm) and correlating measurements to latitude/longitude coordinates during flight,” AGA writes. “Variances come from the different natural gas detection techniques: those that rely on laser or LiDAR technology to collect data, those that rely on infrared camera technology, or those that use a combination of both.”
LiDAR technology uses a specific wavelength of light to scan the target and detect natural gas. This generates geo-registered imagery that, when combined with advanced analytics and other data, helps to create maps of gas leaks and emissions rates. The infrared camera technology creates two wavelengths of infrared energy, with one wavelength used for gas absorption and the other as a reference wavelength to compensate for the effects of temperature and humidity on the detection system’s output signal.
After the initial cost and setup, the drone should be relatively low maintenance and able to produce precise data quickly. Traditional leak detection methods are usually carried out on foot, by road vehicles, by helicopter, or with satellites. However, the mobility of drones eliminates accessibility challenges at sites with bridges, bodies of water, and dense vegetation.
On to infinity and beyond, or at least to wherever NASA goes. Goodard engineers are improving LiDAR technology to help scientists and explorers with remote sensing and surveying, mapping, 3D-image scanning, hazard detection and avoidance, and navigation, according to NASA. “There are a lot of flavors of LiDAR right now,” said Cheryl Gramling, assistant chief for technology at NASA’s Goddard Space Flight Center in Greenbelt, MD. “It’s such an important technology because of the precision and versatility that it offers.”
One of the improvements Goodard innovators are exploring is the development of “a deployable, segmented telescope to capture the returning light signal using state-of-the-art flat-panel optics organized in foldable, origami-inspired panels.” Research engineer Mark Stephen and researchers at Brigham Young University seek to provide future missions with the benefits of LiDAR technology without the current technologies’ high cost and limited efficiency.
“Most people want really high performance,” Stephen said, “But they want it in a small, light, and power-efficient package. We’re trying to find the best balance and cost matters. Often the cost comes more from the size, weight, and power than it does from the actual development if we’re launching something into space. That is where it gets expensive.”
Stephen is nearing the completion of a three-year project aimed at enhancing lidars, which was funded by a Radical Innovation Initiative grant under Goddard's Internal Research and Development (IRAD) program. Their project has been selected by NASA’s Earth Science Technology Office for additional funding to further improve the technology.
“Typically, LiDAR receivers depend on bulky lenses to capture light, each lens needs a specific curvature and size to bend the light, in addition to the structures that hold the lenses, and other mechanics,” Stephen said. “Larger lenses are more effective, and that is where LiDAR technology tends to get heavy.
“Flat optics use new types of nano-structured materials to manipulate individual photons. These meta-materials allow thin and lightweight optics to perform the same functions as much larger and more expensive three-dimensional counterparts.”
Finally, Levenseat Renewable Energy, a Scottish waste management and recycling company, now has real-time access to material inventory figures and, as a result, efficiently manages its logistics and processing operations after implementing a LiDAR-based solution for inventory tracking, according to Recycling Magazine.
Levenseat’s challenge was that one of their facilities covered nearly 3,000 square meters, and the materials delivered for sorting were constantly in motion. Previously employed inventory methods, such as visual estimation upon delivery and truck counting, were inadequate and resulted in inaccuracies, inefficient processes, and disruptions to operations.
The choice was made for a Volume Monitoring solution based on LiDAR technology that provides real-time material data. “This works by LiDAR sensors emitting several hundred thousand laser pulses per second across a large field of view, systematically scanning the surroundings,” writes Recycling Magazine. “From this, 3D surface images are created, and a perception software accurately calculates the volume.”
Despite the enormous dimensions of the facility, only four LiDAR sensors mounted on the ceiling are needed to collect the data which is then made accessible to the employees via user-friendly dashboards. Thanks to the LiDAR-based inventory tracking, “Levenseat was able to increase efficiency in the storage area and logistics processes. Workflows are now smoother, truck scheduling is more precise, processing machine utilization has been optimized, and processing delays have been minimized. Furthermore, Levenseat is now capable of proactively addressing safety risks, such as an increased fire hazard due to facility overcrowding.”
LiDAR is one of the fastest-growing fields in data science and engineering, revolutionizing how we experience the world. This innovative application of lasers has given us new perspectives on everything from industrial automation to self-driving cars. As the use of this technology increases, so will opportunities for development and growth for countless industries.